Vacuum pump



FIG. 1 is a perspective view of the vacuum pump, showing the present design.

FIG. 2 is a front view thereof.

FIG. 3 is a rear view thereof.

FIG. 4 is a left side view thereof.

FIG. 5 is a right side view thereof.

FIG. 6 is a top view of thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines are included for the purpose of illustrating portions of the vacuum pump that form no part of the claimed design. 

CLAIM The ornamental design for a vacuum pump, as shown and described. 